An impedance of an antenna in a radio frequency (RF) signal transmitter is influenced by variances in the environment surrounding the antenna such as an approach of an automobile or physical contact by a user. Variation in the impedance may cause a mismatch between the impedance of the antenna and that of a power amplifier supplying a signal to the antenna, and may adversely affect the performance of wireless communications. In particular, such mismatch may generate a reflected signal flowing from the antenna to the power amplifier, causing interference among signals within the signal transmitter, and a reduction in performance or efficiency of the signal transmitter.
What is needed, therefore, is an apparatus that overcomes at least the shortcomings of the known signal transmitter discussed above.